1. Field of the Invention
The present invention relates to a blender. In particular, the present invention relates to a blender with cooling/muffling functions.
2. Description of the Related Art
U.S. Pat. No. 5,273,358 discloses a quiet and efficient motor cooling fan assembly for a blender. As illustrated in FIG. 5 of the drawings, the blender includes a base frame 1′, a cover 2′, a muffler housing 3′, a motor 4′, and a fan 5′. The base frame 1′ is hollow and includes a compartment 11′ in an upper central portion thereof for receiving the motor 4′ and a plurality of apertures 12′ for air intake. The cover 2′ is mounted on top of the base frame 1′ and includes a bottom engaged with the base frame 1′. Mounted below a central portion of the base frame 1′ is the muffler housing 3′ for receiving the fan 5′. The muffler housing 3′ includes exit apertures 31′. The motor 4′ fixed in the compartment 11′ includes an upper drive shaft 41′ for driving the mixing blades and a lower driver shaft 42′ for driving the fan 5′. The fan 5′ includes a fan plate 51′ with a plurality of vanes 52′ formed thereon.
When the motor 4′ turns, the mixing blades and the fan 5′ are turned, and ambient cool air is sucked into the cover 2′ via the apertures 12′ of the base frame 1′ into the compartment 11′ for cooling the motor 4′. The hot air passing through the motor 4′ flows downward and exits the muffler housing 3′ via the exit apertures 31′, as indicated by the arrows in FIG. 5. However, the hot air exiting the muffler housing 3′ flows toward an outer side of the base frame 1′ and is thus driven into the cover 2′ again via the apertures 12′ of the base frame 1′. The cooling effect of the motor 4′ is thus adversely affected. Further, the cool air driven by the fan 5′ slows down when entering the cover 2′ with a larger volume. Further, the travel for the ambient airflow to the motor 4′ is relatively long and thus adversely affects the cooling effect for the motor 4′, as the velocity of the airflow is reduced.